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This SAE Aerospace Standard (AS) contains requirements for a digital time division command/response multiplex data bus, for use in systems integration that is functionally similar to MIL-STD-1553B with Notice 2 but with a star topology and some deleted functionality. Even with the use of this document, differences may exist between multiplex data buses in different system applications due to particular application requirements and the options allowed in this document. The system designer must recognize this fact and design the multiplex bus controller (BC) hardware and software to accommodate such differences. These designer selected options must exist to allow the necessary flexibility in the design of specific multiplex systems in order to provide for the control mechanism, architectural redundancy, degradation concept, and traffic patterns peculiar to the specific application requirements.

This SAE Aerospace Standard (AS) contains requirements for a digital time division command/response multiplex data bus, for use in systems integration that is functionally similar to MIL-STD-1553B with Notice 2 but with a star topology and some deleted functionality. Even with the use of this document, differences may exist between multiplex data buses in different system applications due to particular application requirements and the options allowed in this document. The system designer must recognize this fact and design the multiplex bus controller (BC) hardware and software to accommodate such differences. These designer selected options must exist to allow the necessary flexibility in the design of specific multiplex systems in order to provide for the control mechanism, architectural redundancy, degradation concept, and traffic patterns peculiar to the specific application requirements.

The Cardinal is a Super Short Takeoff and Landing (SSTOL) aircraft, which is designed to fulfill the desire for center-city to center-city travel by utilizing river “barges” for short takeoffs and landings to avoid construction of new runways or heliports. In addition, the Cardinal will fulfill the needs of the U.S. Navy for a Carrier On-board Delivery (COD) aircraft to replace the C-2 Greyhound. Design requirements for the Cardinal included a takeoff ground roll of 300 ft, a landing ground roll of 400 ft, cruise at 350 knots with a range of up to 1500 nm with reserves, payload of 24 passengers and baggage for a commercial version or a military version with a 10,000 lb payload, capable of carrying two GE F110 engines for the F-14D, and a spot factor requirement of 60 feet by 29 feet.

Preliminary results from testing of 26 X 6.6 radial-belted and bias-ply aircraft tires at NASA Langley's Aircraft Landing Dynamics Facility (ALDF) are reviewed. These tire tests are part of a larger, on going joint NASA/FAA/Industry Surface Traction and Radial Tire (START) Program involving three different tire sizes. The 26 X 6.6 tire size evaluation includes cornering performance tests throughout the aircraft ground operational speed range for both dry and wet runway surfaces. Static test results to define 26 X 6.6 tire vertical stiffness properties are also presented and discussed.

The transition towards More Electric Aircraft (MEA) architectures has challenges relating to integration of power electronics with the starter generator system for on-engine application. To efficiently operate the power electronics in the hostile engine environment at high switching frequency and for better thermal management, use of silicon carbide (SiC) power devices for a bi-directional power converter is examined. In this paper, development of a 50 kVA bi-directional converter operating at an ambient temperature of about 2000C is presented. The design and operation of the converter with details of control algorithm implementation and cooling chamber design are also discussed.

Certain standard parts in the aerospace industry require qualification as a prerequisite to manufacturing, signifying that the manufacturer’s capacity to produce parts consistent with the performance specifications has been audited by a neutral third-party auditor, key customer, and/or group of customers. In at least some cases, a certifying authority provides manufacturers with certificates of qualification which they can then present to prospective customers, and/or lists qualified suppliers in a Qualified Parts List or Qualified Supplier List available from that qualification authority. If this list is in an infrequently updated and/or inconsistently styled format as might be found in a print or PDF document, potential customers wishing to integrate qualification information into their supplier tracking systems must use a potentially error-prone manual process that could lead to later reliance on out-of-date or even forged data.

Aviation industry is striving to leverage the technological advancements in connectivity, computation and data analytics. Scalable and robust connectivity enables futuristic applications like smart cabins, prognostic health management (PHM) and AI/ML based analytics for effective decision making leading to flight operational efficiency, optimized maintenance planning and aircraft downtime reduction. Wireless Sensor Networks (WSN) are gaining prominence on the aircraft for providing large scale connectivity solution that are essential for implementing various health monitoring applications like Structural Health Monitoring (SHM), Prognostic Health Management (PHM), etc. and control applications like smart lighting, smart seats, smart lavatory, etc. These applications help in improving passenger experience, flight operational efficiency, optimized maintenance planning and aircraft downtime reduction.

Airline tenants at Dallas/Fort Worth International Airport (DFW Airport) use deicing/anti-icing chemicals, as may be needed, to maintain wintertime operations. DFW Airport has implemented best management practices for pollution prevention measures relating to deicing/anti-icing activities. However, as the planes leave the deicing pads, deicing/anti-icing fluids can drip from the planes onto the runways, taxiways, and ramp areas. As planes take off, the fluids can also shear off onto Airport property. During winter storm events, these deicing/anti-icing fluids are flushed off the runways, etc., with the stormwater. Stormwater containing deicing/anti-icing fluids can discharge through outfalls into Trigg Lake located in the southwestern part of the DFW Airport property.

Abstract Identity-Anonymized CAN (IA-CAN) protocol is a secure CAN protocol, which provides the sender authentication by inserting a secret sequence of anonymous IDs (A-IDs) shared among the communication nodes. To prevent malicious attacks from the IA-CAN protocol, a secure and robust system error recovery mechanism is required. This article presents a central management method of IA-CAN, named the IA-CAN with a global A-ID, where a gateway plays a central role in the session initiation and system error recovery. Each ECU self-diagnoses the system errors, and (if an error happens) it automatically resynchronizes its A-ID generation by acquiring the recovery information from the gateway. We prototype both a hardware version of an IA-CAN controller and a system for the IA-CAN with a global A-ID using the controller to verify our concept.

The vision of SESAR is to integrate and implement new technologies to improve air traffic management (ATM) performance. Enhanced automation and new separation modes characterize the future concept of operations, where the role of the human operator will remain central by integrating more managing and decision-making functions. The expected changes represent challenges for the human actors in the aircraft and on ground and must be taken into account during the development phase. Integrating the human in the ATM system development starting from the early design phase is a key factor for future acceptability. This paper describes the adaptation of currently applied Cockpit Human Factors processes in order to be able to design the aircraft for the future ATM environment.

The objective of this paper is to show the probable composition of the VTOL Transportation System of the future and provide some specific predictions concerning some of its key elements. Two types of service are recognized: metropolitan area service, connecting airports with downtown and suburban heliports -- which will continue to be done by helicopters; and inter-city downtown to downtown service employing high speed future type VTOL aircraft. Currently operating VTOL airlines are demonstrating the practicality of metropolitan area helicopter service. Advanced, high speed VTOL vehicles, introduced in the 1970’s will make extension of current routes possible to inter-city service. To fully develop the potential in the future, large “transportation centers” will be established in our major cities.

The use of control architectures with the Integrated Modular Avionics (IMA) concept (“IMA architectures”) in aerospace and the Integrated Modular Electronics (IME) concept (“IME architectures”) in automotive applications is growing due to its reduced number of hardware such as processors, Line Replaceable Units (LRUs) and Electronic Control Units (ECUs), thereby reducing weight and costs. Furthermore, IMA architectures can perform complex reconfigurations in the case of failures and adapt themselves to changes in network functioning or operating modes, which make a control system very robust. The objective of this work is to discuss the use of an IMA architecture to simulate an aerospace control system responsible for maintaining a vehicle in a predetermined trajectory. To do that, we review the current literature related to IMA architectures and give an overview of their characteristics. Then, we choose an aerospace control system and discuss its simulation using an IMA platform.

The SCARLETT European Research Project has the goal to define, develop and validate the concepts of the next generation of IMA (IMA2G). Enhanced File Management capability is central to support next generation IMA Platform properties and the increasing usage of memory mass storage. IMA2G Applications require access to data stored on mass memory independent from their physical location across the Platform; Platform-wide File Services are required. We provide, in the framework of the SCARLETT project, a distributed approach to File Management, which meets the IMA2G requirements. The proposed design aims to move from a module-centric File Management, typical in IMA1G, to a Platform-centric File Management based on a distributed file stack. After examining existing IMA standard solutions concerning File Management, an overview of the ‘Platform File Management’ architecture is given.

A study has been conducted into the employment of ailerons as a brake augmentation device capable of minimising landing distance whilst maintaining the aircraft on the runway centre line. The idea is to use ailerons to increase the normal force on the undercarriage, which has the effect of increasing the available friction force in favour of the gear that is most likely to skid. The paper evaluates, the aerodynamic forces and moments produced by ailerons, the achievable increase/decrease in the applied normal undercarriage loading, the aircraft roll rates, dynamic lags due to fully deflecting the ailerons, and the responsiveness of the anti skid system. This paper shows that the ailerons have the aerodynamic effectiveness to enhance differential braking and describes the concept for shortening landing distances. The paper introduces the methodology to achieve this proposed effect.

The strategic planning and tactical execution of Air Traffic Control (ATC) provided by Air Navigation Service Providers (ANSP) are often not aligned and lead to inefficiencies in the Air Traffic Management (ATM) system. This paper proposes an analytical framework for the air traffic control system based on a system-of-systems paradigm, with a hierarchy of nested and cascaded feedback control loops—one or more for each type of control service. The framework is then used to assess the stability and response to random variables, such as poor weather and equipment failures. The performance of each control loop is then described qualitatively and validates the framework for investigating the benefit of new policies and technologies.

The objective of this work is to better understand freezing fog/drizzle conditions using observations collected during the Fog Remote Sensing and Modeling project (FRAM-S) that took place at St. John's International Airport, St. John's, NL, Canada. This location was ~1 km away from the Atlantic Ocean coast. During the project, the following measurements at one minute resolution were collected: precipitation rate (PR) and amount, fog/drizzle microphysics, 3D wind speed (Uh) and turbulence (Uh'), visibility (Vis), IR and SW radiative fluxes, temperature (T) and relative humidity (RH), and aerosol observations. The reflectivity and microphysical parameters obtained from the Metek Inc. MRR (Microwave Rain Radar) were also used in the analysis. The measurements were then used to obtain freezing fog/drizzle microphysical characteristics and their relation to visibility.

Assuming the delivery with an excess velocity reserve 3.300 ft/sec of a 1 ton. transferable load to a space laboratory orbiting at 200 S.M., the feasibility of a 2 (or 3) stages “horizontal take-off transporter” is considered. Analysis includes the concept of two recoverable vehicles and discusses the configuration, separation, return and propulsion. Design assumes that conventional airports can be used without special facilities, except LOX and LH.

AiResearch has investigated the application of high-speed turbocompressor technology to the space station airlock gas recovery system. Design studies have shown that multi stage centrifugal compressors can complete the airlock evacuation cycle in half the time and at one-third the weight of traditional positive-displacement vacuum equipment. The key elements of this technology are the self-acting gas bearing and the permanent magnet motor. The compliant foil bearing uses the lip speed of the rotor to pump the surrounding air into the lubricating film. The bearings are free of potential contaminates to the station air as no other lubrication is needed. The permanent magnet brushless dc motor allows the compressor to operate at the high rotational speeds needed for efficient aerodynamics. To provide a simple control method the motor operates at constant torque during the airlock evacuation cycle.